People protest the Keystone XL oil pipeline at a rally in San Francisco in November. / AFP/Getty Images

by Wendy Koch, USA TODAY

by Wendy Koch, USA TODAY

The controversial Keystone XL pipeline hit another obstacle Wednesday when a judge struck down a Nebraska law that allowed the oil pipeline to cross the state.

Lancaster County Judge Stephanie Stacy issued a ruling that invalidated Nebraska Gov. Dave Heineman's approval of the route. Stacy said the law unconstitutionally gave the governor authority to approve the route and to allow the oil pipeline company to seize land via eminent domain from Nebraska landowners.

Stacy, siding with three landowner plaintiffs, said authority rests with the Nebraska Public Service Commission, which regulates pipelines and other utilities. His ruling bars Heineman from using the law to advance the pipeline.

The ruling could cause further delays for Keystone XL, which would carry heavy tar sands oil from Canada's Alberta region to the Midwest. Calgary-based TransCanada has been seeking a U.S. permit for the project for years, but lengthy environmental reviews by the State Department have delayed a final decision. President Obama was widely expected, prior to this ruling, to approve or reject the pipeline this year.

"This Nebraska court decision adds a new, major roadblock to the Keystone XL pipeline review process," said Daniel Weiss of the Center for American Progress, a liberal-leaning research group that opposes the project. He said he expects Obama probably will wait until Nebraska has legally approved the pipeline route before approving a permit.

"We are disappointed and disagree with the decision," said TransCanada spokesman Shawn Howard. "We will now analyze the judgment and decide what next steps may be taken. "

TransCanada says the billion-dollar project will provide thousands of U.S. jobs and will provide a "secure supply of crude oil from a trusted neighbor." Environmentalists say tar sands is a particularly dirty fuel and its development would exacerbate global warming

Dave Domina, the lawyer who handled the case for the landowners, said in a statement that the ruling is "not about the merits of any pipeline in particular" but is instead "a landowner rights case."